煤基多联产系统CO2控制一体化技术理论基础研究

Polygeneration system for chemical and power has been regarded as one of promising technologies to use fossil fuel more efficiently and cleanly. Nowadays, anthropogenic emissions of CO2 into the atmosphere are mainly caused by combustion of fossil fuels, among them coal plays an important role in the survival and evolution of human society. We take into consideration of CO2 emission mainly from coal-fired-power plants, two ways of CO2 emission control are suggested in this project. One is CO2 conversion technology combined with the polygeneration system. This system does not require a CO2 separation unit. The system avoids the conventional water-gas shift reaction that is used to adjust the ratio of C/H in the syngas, but fully uses the CO2 produced from coal gasification, which solves the problems of CO2 capture and storage; another is CO2 separation from power generation. Both of them are evaluated by a new optimization method for polygeneration system integration with CO2 emission control in this project. To clarify the internal mechanisms among the CO2 emission reduction, energy efficiency and elements' utilization in the polygeneration system will determine the best starting point of separation or unit process technology. Element utilization and energy utilization were presented as the objective functions simultaneously; parameter variations and technology conditions were performed to investigate the influence of each unit specific operation conditions on the performance of the system by Aspen Plus. The treatment of multi-objective values selection will be discussed as well. The new optimization method proves to be an effective to solve multi-objective optimization problems. We will focus on the COx formation, migration and enrichment in the co-production system. By the theoretical calculation, process simulation analysis (Aspen Plus) and experimental researches, we will establish the energy system integrated optimization theory with CO2 emission control to meet the requirements of the energy production rationalization, the elements utilization maximized, the environmental pollution minimized, and the maximum economic benefit. In the end, to develop a newly designed CO2 emission control technology integrated with coal-based polygeneration system.

煤基化工动力多联产系统通过单元过程革新和优化集成，是实现煤炭能源高效洁净利用、可持续发展的核心技术之一。项目立足实现CO2减排控制技术与多联产系统的有机耦合，以研究新型煤基化工动力多联产CO2控制一体化能源利用模式为主要目标，着重考察系统中COx的生成、迁移和富集过程中的能流、物流的变化，阐明CO2减排-能量-元素内在机制和联系，分析CO2分离和CO2转化利用的两种CO2减排控制模式对联产系统能量利用效率和元素利用效率的影响机理，确定CO2在联产系统中的迁移、转化、循环、分离的最佳切入点和工艺技术路线。采用理论计算、流程模拟分析与实验研究相结合，通过能源动力系统综合评价指标和方法，建立系统集成优化理论，解决煤炭资源生产过程中能量利用合理化、元素利用最大化、环境污染最小化和经济效益最大化的整体最优工况，实现新型CO2减排控制技术一体化煤基多联产系统集成创新。

通过分析COx的生成、迁移和富集过程中的能流、物流的变化，揭示了CO2减排-能量-元素内在机制和联系，初步阐明了CO2分离和CO2转化利用的两种CO2减排控制模式对联产系统能量利用效率和元素利用效率的影响规律；初步构建了基于CO2转化利用技术的能源动力系统综合评价指标，创建了由单目标向多目标转移的系统性能集成优化模拟平台与方法，实现了系统工艺条件、操作参数、系统配置等条件的集成优化选择，进而达到系统在能量利用、元素利用、经济效益和CO2减排等综合性能方面整体最优化的目标，形成了具有普适性的煤基多联产与CO2循环利用减排控制一体化集成优化理论分析方法雏形。在此基础上，根据煤炭及其伴随矿产资源的组成特征，提出了富含CH4焦炉煤气与富含CO2气化煤气循环转化利用一体化工艺流程；基于商业化的CO2循环转化利用及富氧燃烧技术，提出了CO2循环利用耦合富氧燃烧煤基多联产系统，设计并验证了CO2捕集与循环利用的甲醇联产电力的多联产系统的节能减排优越性。立足解决焦化行业产业链过程中的“排碳”和“补碳”矛盾，提出了炼焦-污染物排放控制-化学品合成一体化的低碳循环焦化转化集成系统技术路线。通过对不同煤基能源转化系统与CO2减排控制的集成与工艺优化研究，系统地阐明了煤基能源生产系统过程中CO2循环利用可以有效实现煤炭转化源头节煤、节水，中间过程元素互补匹配、能量梯级利用，终端产品提质（值）和减排CO2的协同。